Lots of applications use a network of small, rather cheap, battery-operated sensor devices, such as fire detectors, occupation sensors, movement sensors, temperature sensors, humidity sensors, light intensity sensors, etc. These sensors, or more generally embedded devices, generate information or receive, process and transmit information encapsulated in packets to network nodes with more extensive processing capabilities. The latter nodes may be rather simple, e.g. light switches, or may be more complex, e.g. heating controllers.
Since embedded devices such as sensors are usually battery-operated, passed efforts have been focusing on reducing the energy consumption. In the article “Broadening the Concept of Aggregation in Wireless Sensor Networks”, the authors Eli De Poorter, Stefaan Bouckaert, Ingrid Moerman and Piet Demeester for instance propose global aggregation, i.e. combining information from different sources, different network layers and different protocols into a single information packet, in order to reduce the overall amount of transmissions in wireless sensor networks thereby increasing the energy efficiency and network lifetime.
Although Eli De Poorter et al. suggest protocol and layer independent aggregation, excessive memory and processing resources are still consumed in each network node for handling the information packets as a result of the redundancy in overhead introduced at different layers of the protocol stacks.
International Patent Application WO 2007/130004 entitled “Smart Data Dissemination” addresses the problem of heterogeneous data formats and transport mechanisms in networks with large amounts of inexpensive, energy-constrained sensor devices. WO 2007/130004 therefore proposes a wireless sensor network wherein each wireless network node maintains a set of XML configurable, predetermined rules that define the processing of received data based on data characteristics, network conditions and device conditions. This way, different nodes in the WSN can handle a single data packet differently, i.e. optimally process the data packet depending on network, traffic and device conditions.
Although WO 2007/130004 enables different processing in various nodes, e.g. unicast vs. broadcast, data compression or fusion, etc., taking into account the measured or actual traffic and network conditions, it does not cope with the heterogeneity in protocols, network layers and data formats, and certainly does not ensure always optimal connectivity and protocol independent quality of service.
U.S. patent application US 2006/0221929 entitled “Description of Packet in a Packet Communication Network” describes a router that maintains or has access to a database of data descriptors, 21 in FIG. 2 of US 2006/0221929. Upon receipt of a data packet, the router processes the packet as a function of the data descriptor, independent of the protocol. The data descriptors are sent to the router via separate packets or via a signalling channel. Each received data packet further contains an identifier of the relevant data descriptor in the database.
Although the router known from US 2006/0221929 receives protocol independent information on the type of data, source and addressee, enabling to apply dedicated processing, the underlying network technology remains IP (Internet Protocol). The technique described in US 2006/0221929 requires a standardized way to communicate data descriptors in IP packets or over a signalling channel, is therefore not backwards compatible, and at best enables an IP router to make abstraction of the layer 4 to 7 protocols. In other words, US 2006/0221929 does not tackle the heterogeneity in protocols and formats at layers 1-3, and does not guarantee an always-optimal connectivity, including network-to-network connectivity. Moreover, the data descriptors known from US 2006/00221929 describe a method that has to be used to process the data. Protocol specific information like for instance a hop count value is not described by and cannot be updated using the data descriptors.
U.S. patent application US 2005/0180429 entitled “Multi-Service Network Switch with Independent Protocol Stack Architecture” describes dynamic bonding of layer two protocols to physical interfaces at runtime in a smart switch. The smart switch identifies the layer two protocols from the connection request and thereupon configures the bonding to the physical interfaces. This way, layer two protocols become independent of the physical interface they are running on.
Just like the above listed prior art solutions, US 2005/0180429 fails to provide an answer to the heterogeneity of data formats and protocols at the different network layers. It cannot connect any network technology to any other network technology thereby ensuring an always optimal connectivity.
It is an objective of the current invention to disclose a node for generating or receiving, processing and transmitting information that overcomes the above mentioned shortcomings of prior art solutions. In particular, it is an objective to disclose such node that takes into account the heterogeneity of information formats, network layers and protocols used in the network, and that supports energy-efficiency and protocol independent quality of service (QoS). It is a further objective to support an always optimally connected strategy at all network levels. It is yet another objective to disclose a node and architecture that can connect any network technology with any other network technology, supporting next generation applications for e.g. wireless sensor networks while remaining backwards compatible with existing protocol stacks and legacy networks. It is also an objective to further increase the throughput and network lifetime.